renaming BoundaryHandler to PoissonBoundaryHandler, defining new base…

… class ES and derived ExplicitES

Source/FieldSolver/ElectrostaticSolvers/ElectrostaticSolver.H

@@ -0,0 +1,23 @@
+/* Copyright 2024 Roelof Groenwald, Arriana Formenti, Revathi Jambunathan
+ *
+ * This file is part of WarpX.
+ *
+ * License: BSD-3-Clause-LBNL
+ */
+#ifndef Electrostatic_Solver_H_
+#define Electrostatic_Solver_H_
+
+class ElectrostaticSolver
+{
+    public:
+
+    ElectrostaticSolver() = default;
+
+    ComputeRHS() = default;
+
+    PoissonBoundaryHandler m_poissonboundaryhandler;
+
+}
+
+#endif
+

Source/FieldSolver/ElectrostaticSolvers/ElectrostaticSolver.cpp

@@ -0,0 +1,7 @@
+#include "ElectrostaticSolver.H"
+#include "PoissonBoundaryHandler.H"
+
+ElectrostaticSolver::ElectrostaticSolver ()
+{
+    m_boundaryhandler = std::make_unique<PoissonBoundaryHandler>();
+}

Source/FieldSolver/ElectrostaticSolvers/ExplicitES.H

@@ -0,0 +1,6 @@
+#include "ElectrostaticSolver.H"
+
+class ExplicitES () : public ElectrostaticSolver
+{
+
+}